The present disclosure relates to oil and gas exploration and production, and more particularly to a subassembly for storing and releasing a wiper plug into a work string.
Wells are drilled at various depths to access and produce oil, gas, minerals, and other naturally-occurring deposits from subterranean geological formations. Hydrocarbons may be produced through a wellbore traversing the subterranean formations. Under certain subterranean conditions, completing a well to produce hydrocarbons involves applying cement to a wellbore or wellbore casing.
In a cementing operation, cement may be delivered downhole through a work string and circulated back uphole in an annular space between a casing and wellbore wall. In some instances, multiple segments of the annular space may be cemented in different stages. Prior to starting cementing operations in all or a segment of a wellbore, it may be desirable to prepare the well for cementing by removing debris from the wellbore and separating the cement from other fluids in the wellbore. Similarly, following cementing, it may be desirable to clear the work string and inside of the casing of cement prior to resuming formation or completion operations.
To prepare the wellbore and prevent the cement from mixing with other fluids, a spacer fluid followed by cementing plugs or darts may be released downhole in advance of the cement flow. To clear the work string and casing, a second plug or dart may be released after the cement to wipe clear the inside of the work string and casing.